Why do some iron objects such as ships float when placed in water while other iron objects such as nails sink? 1. iron ships have large air pockets inside them, making them less dense than water and thus able to float. 2. the same reason that makes planes fly in the sky?

The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.

Which statement is true if the refractive index of medium a is greater than that of medium b? a. total internal reflection is possible when light travels from air to medium b to medium a. b. total internal reflection is possible when light travels from medium a to medium b. c. total internal reflection is possible when light travels from medium b to medium a. d. total internal reflection is possible when light travels from air to medium a. e. total internal reflection is possible when light travels from air to medium b.

Suppose that the half-life of an element is 1000 years. how many half-lives will it take before one-eighth of the original sample remains? 8 125 12.5 3